Ridley's engineers set out on a new mission right on the heels of the Helium's release. The goal was to maintain the stiffness and stability of the proven original, while at the same time reducing its overall weight. The result of their efforts is the aptly-titled Helium SL. At around 1050 grams with the fork, the SL frameset rests squarely at the front of the market's low-weight frame offerings. And while most sub-800 gram frames are more akin to wet noodles, the SL is responsive and bred for racing in the mountains. And now, finely tuned with a full Shimano build kit, the Helium SL/Shimano Ultegra Complete Road Bike - 2014 is eager to launch you up the steepest of climbs with ease. Starting with the weight, the SL sees a 150 gram decrease from the last iteration of the Helium. This was achieved through the use of a more sophisticated carbon selection, this time utilizing a strategic placement of 60, 40, and 30 ton high-modulus carbon fiber. Before the SL, the Helium featured a predominately 30 ton carbon composition. Why is this important Well, for a refresher, the 'ton' designation in '60 ton' refers to the carbon's ability to withstand 60 tons of pressure per square millimeter. So, basic logic tells us that a stronger carbon fiber requires less carbon to be used -- as is the case with the SL. And on top of the carbon, Ridley bonded the carbon with a nano resin this time around. This further reduced weight, and it also increased the strength of the construction. Not surprisingly, Ridley wasn't done yet. To further reduce weight, Ridley constructed the front triangle of the SL with a monocoque design. This means that the entire front triangle (head tube, down tube, seat tube, and bottom bracket lug) is made in one piece. How does this save weight Well, with the current SL system, the seatstays, chainstays, and dropouts are bonded to the existing triangle by applying resin and then over-wrapping the bonding points with more carbon fiber. With the SL, this ap...